Filtration device for a waste water treatment system

ABSTRACT

A filter and housing ( 10 ) for waste water treatment includes a housing ( 10 ) having a plurality of coaxially mounted vertically extending sections adaptable to receive a filter cartridge therein. An upper section ( 12 ) is provided with an outlet consisting of at least two coaxially aligned rings ( 22 ) of preselected diameters wherein the thickness of the rings and the spacing between the rings is sufficient to receive waste water treatment outlets of different diameters. The filter cartridge is comprised of a stacked arrangement of a plurality of disc-dam units ( 32 ) wherein each disc-dam unit ( 32 ) is provided with a serpentine configured first dam ( 46 ), the first dam extending upwardly from an upper surface of the disc-dam unit, the first dam having terminating ends spaced at outer terminating edges ( 34   a,    34   b ) of the disc dam unit to define a cord segment therebetween. The terminating ends are connected by a second dam ( 46 ) having a height less than the first dam. The serpentine configured first dam divides the disc-dam unit into an upstream side along the outer periphery and a downstream side along the inner periphery. Slots are positioned within the serpentine configured dam on the upstream side thereby providing flow communication with underlying disc-dam units. The top of the first dam is of a preselected height so as to provide a preselected spacing between the top of the first dam and the under surface of an overlying disc-dam unit.

TECHNICAL FIELD

[0001] The present invention relates to a filter and filter housing foruse in a waste water treatment system and more particularly relates to asectionalized filter housing having capability of receiving filtercartridges of various lengths and is adaptable for connecting to watertreatment tank outlet pipes of varying diameters.

BACKGROUND OF THE INVENTION

[0002] In the treatment of waste water, particularly in septic tanks, itis common to install filters to remove particulates being dischargedfrom the tank which are generally undigested solids so that thedischarging effluent is a relatively colorless and harmless liquid.There have been a number of filter units designed over the years for theremoval of these undigested solids from the waste water prior todischarge from a septic tank or the like. For example, U.S. Pat. Nos.2,900,084; 3,332,552; and, 4,710,295 to Robert Zabel teach a waste watertreatment filtration system which includes a plurality of disc-dam unitsdisposed in a stack, vertically spaced, in a super-imposed relationshipsuch that the bottom of each overlying disc-dam unit cooperates with theupper edges of each underlying unit to form a horizontally elongatedvertically narrow outlet slots. The stack of disc-dam units are mountedin a cylindrical housing with several slots located above and severalslots located below the liquid operating level in a waste water tank. Inoperation, the digested waste water is received through a bottom openingof the housing and the discharging clarified effluent flows through asidewall outlet which is in flow communication with an outlet from thewaste water tank. However, it has been found that septic tanks or wastewater treatment tanks come in different sizes and capacities and alsothe outlet discharge from the waste water tank is not of a standardsize. Thus, for residential and commercial applications it is difficultto provide a filter housing unit of varying filtration capacities andwith discharge outlets adaptable to mate with the various sizes ofoutlet discharge pipes or conduits from the waste water treatment tank.

SUMMARY OF THE INVENTION

[0003] It is an object of the present invention to provide a filterhousing for a waste water treatment tank that includes a plurality ofvertically extending interchangeable sections which allows for thedesign of a filter housing providing for a filtration system ofdifferent filtering capacities.

[0004] It is another object of the present invention to provide a filterhousing have an outlet which is adaptable for mating with waste watertreatment tank outlets of different sizes.

[0005] It is a further object of the present invention to provide afilter housing which is relatively inexpensive and easy to install.

[0006] It is even a further object of the present invention to provide afilter cartridge of disc-dam filter units in a filter housing thatreduces turbulence during the upflow of waste water in the cartridge.

[0007] It is also an object of the present invention to provide a filtercartridge of disc-dam filter units wherein the discs have a diameter ofless than ⅛″ of the inside diameter of the filter housing.

[0008] More particularly, the present invention provides a filter and ahousing for a waste water treatment system wherein the housing includesat least an upper section with an outlet for flow communication with awaste water treatment tank discharge outlet and a lower section with anopen bottom to receive upward flow therethrough. The upper section ismounted above the lower section and there may be a plurality of middlesections mounted between the upper section and the lower section toaccommodate filter cartridges of various lengths. Each of the sectionsof the housing include means to receive a plurality of disc-dam unitstherein. The plurality of disc-dam units in a stack arrangement definethe filter cartridge with a longitudinally extending axis. Each of thedisc-dam units is of a generally circular-shaped disc having an outerterminating edge, the base portion of each unit having a planar undersurface and an upper surface with a first dam of serpentineconfiguration having a first and second terminating end. The dam whichextends upwards from the upper surface of the base portion terminates ina dam top whereby a preselected distance is defined between the dam topand the under surface of an overlying disc. The first end and the secondend of the dam define a cord segment therebetween, the dam dividing thebase portion into an upstream and downstream side, the upstream sidebeing along an outer periphery of the base portion and the downstreamside being along an inner periphery of the base portion. The cordsegment provides a cut out which extends from a second dam whichconnects the first and second ends of the outer terminating edge of thefirst dam wherein the second dam has a height less than the height ofthe first dam. Moreover, each of the discs are provided with a pluralityof upstream openings in the upstream side of the base portion which arein flow communication with an adjacent underlying disc-dam unit. Theflow through openings are generally positioned within the serpentineconfigured dam. The cut-outs of each disc are aligned to form an outletflow chamber which is in flow communication with an outlet waste watertreatment tank discharge outlet.

[0009] The lower section of the housing is provided with an inwardlyextending sealing edge positioned for alignment with the disc-dam unitcut outs. The sealing edge is in contacting relation with the lowermostdisc-dam unit wherein the sealing edge covers the cut out of thelowermost disc-dam unit thereby sealing the bottom of the outlet flowchamber from the incoming waste water to be filtered.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] A better understanding of the invention will be had uponreference to the following description in conjunction with theaccompanying drawings in which like numerals refer to like partsthroughout the several views and wherein:

[0011]FIG. 1 is a perspective view, with selected portions shownexploded, of a preferred filter and housing of the present invention;

[0012]FIG. 2A is a perspective view of one preferred disc-dam unit ofthe present invention;

[0013]FIG. 2B is a perspective view of another disc-dam unit of thepresent invention;

[0014]FIG. 2C is a perspective view of a lid for the filter cartridge ofthe present invention;

[0015]FIG. 3 is a side elevational view, in section, of the arrangementshown in FIG. 1 in assembled form;

[0016]FIG. 4A is an enlarged segmental view showing a method ofoperation of the filter assembly shown in FIG. 1;

[0017]FIG. 4B is an enlarged segmental view of the orientation of thediscs of the present invention received within the lower section of thehousing, as shown in an assembled unit of FIG. 1;

[0018]FIG. 5A is a perspective view of a lower section of the filterhousing of FIG. 1;

[0019]FIG. 5B is a perspective view of a middle section of the filterhousing of FIG. 1 with selected portions shown in phantom lines;

[0020]FIG. 5C is a perspective view of an upper section of the filterhousing of FIG. 1;

[0021]FIG. 6 is a view of the arrangement of the filter housing assemblyshown in FIG. 1 in a waste water treatment tank;

[0022]FIG. 7 is a perspective view of another embodiment for a disc-damunit of the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0023] Referring to FIG. 1, which is an exploded perspective view of onepreferred embodiment of the present invention, a filter housing 10includes a plurality of sections mounted one on top of the other. Asshown, the filter housing 10 is provided with an upper section 12mounted above and onto a middle section 14 which, in turn, is mountedabove and onto a lower section 16. Each of the sections are of the samediameter and are made of any suitable material, such as a thermo-plasticmaterial, which is well known in the art. An outlet discharge isprovided on the upper section and is generally comprised of a pluralityof rings, such as rings 20 and 22, of a preselected size and thicknessso that the outlet discharge from the upper section 12 can receive in amale or female arrangement a plurality of waste treatment dischargeoutlets of different diameters. Even though two rings 20 and 22 areshown, it is realized that additional rings may be provided at theoutlet from the upper section 12 to accommodate even a larger number ofwaste water treatment outlets.

[0024] Within the filter housing sections 12, 14, 16, a plurality ofdisc-dam units 32 are in a vertically spaced arrangement, as best shownin FIG. 3. A filter cartridge is comprised of a plurality of filterdiscs or disc-dam units 32 of generally circular cross section with acut out cord section which is defined by a dam 46 which connects withterminating edges 34 a and 34 b of a serpentine configured dam 36 andthe inner surface of the sections of the housing, such as upper section12 as shown in FIG. 1. Each disc-dam unit is in parallel with overlyingand underlying discs 32 with interlocking connectors 50 wherein theconnectors 50 are of preselected configuration to provide a spacebetween the dam top 44, and the under surface 42 of an overlying disc32, as best shown in FIG. 3. The disc 32 is generally made of a suitablematerial, such as a thermoplastic material. Also, discs 32 have adiameter as close as possible to the inside diameter of the housingsections 12, 14, 16 as practical. The discs 32 diameter are generallywithin ⅛″ of the inside diameter of housing sections 12, 14, 16 toprevent upflow of solids along the outer periphery of the filtercartridge.

[0025] As shown in FIG. 2A, a disc-dam unit 32 comprises an elongatedover-flow dam 36 which extends from one of the edges identified as 34 aor 34 b to the other terminating edge 34 a or 34 b in a serpentine orsinuous path on the upper surface 40 of the disc 32. The dam 36 extendsvertically upward a preselected distance and in a stacked arrangementdefines a spacing between the top 44 of the dam 36 and the under surface42 of the overlying disc 32. On one side of the dam 36 is an upstreamportion which receives upwardly flowing non-filtered material throughelongated slots 38 which are generally located within the curved portionof the sinuous path of the dam 36. Positioning the inlet slots 38 in thecurved portion of the sinuous path provides an upwardly flowing flowpath that is not subjected to turbulence as it flows vertically and overthe top 44 of the dam 36 and into the downstream side which is definedby the inner periphery of the sinuous path of the dam 36. The outerperiphery of the disc 32 and the outer surface of the dam 36 define theupstream portion. The serpentine configured dam 36 terminates with aterminating edge 34 a at one end and with a terminating edge 34 b at anopposed end. The terminating edges 34 a and 34 b are connected by asecond or outlet dam 46 wherein the outlet dam is of a height less thanthe height of the serpentine configured dam 36. Thus, the flow offiltered fluid from the downstream side or inner portion of the discoverflows the dam 46 and into the outlet chamber 28 which is defined bythe stacked arrangement of the discs 32 and the dam 46 terminating edges34 a and 34 b in sealing relation with seal members 24 a, 24 b, 24 c, asshown in FIGS. 5A, 5B and 5C. This arrangement defines the outletchamber 28 for receiving the filtered waste water from the filtercartridge. The chamber 28 is in flow communication with the outlet 19from the waste water treatment tank 19 (FIG. 6). Centrally located ineach of the discs is an opening 48 to receive a support pipe 60 (FIG. 3)therethrough.

[0026] The discs 32 are also provided with notches 52 for engaging withlobes 54 a, 54 b, and 54 c, of the filter sections 12, 14 and 16 (FIGS.5A, 5B and 5C). The lobes 54 a, 54 b, and 54 c, and the pipe 60 on whichthe disc-dam units 32 are mounted, in alignment with the interlockingconnectors 50, provide for an easy assembly in stable relationshipbetween the plurality of the disc-dams units 32 making up the filtercartridge in a use condition.

[0027]FIG. 2B shows a modification of the disc-dam unit 32 wherein thedisc-dam unit in FIG. 2B is identified by the numeral 132 and the onlydifference is the cut out segment 134. In particular, disc-dam unit 132is generally positioned in the upper portion of the upper section 12 forreceipt of a level alarm, level indicating device, or the like, whichmay be placed within the incoming discharge waste water into the filtercartridge. When a level indicator, level control, level alarm, or thelike, is utilized, the top plate, as shown in FIG. 2C, is utilized asthe top disc of a filter cartridge. This disc, identified by numeral232, is provided with a planar surface 240 with an opening 248 thereinto receive the pipe 60 therethrough. Notches 252 are provided forengagement with the lobes 54 c, particularly in the upper section 12.Connectors 250 are also provided for alignment and inner connecting withthe disc 232 and an underlying disc 132. Moreover, cut-outs 234 a and234 b are provided for alignment with terminating edges 34 a and 34 b ofthe discs 32 and 132 and are received by the sealing members 24 c in theupper filter housing section 12. Cut-outs 236 and 238 are also providedin case of an overflow so that the disc 232 does not have an overflow ofwaste water in case the liquid level exceeds the top of the filtercartridge.

[0028] Upwardly extending coupling 254 is provided to receive the levelcontrol, level alarm, level indicating means and the like. The coupling254 is in alignment with the cut-out 134 in the disc 132.

[0029]FIGS. 5A, 5B and 5C show the details of the three differentsections which make up the housing of the filter housing 10. Each of thehousing sections 12, 14 and 16 have means to connect to one another in astacking arrangement. In a preferred embodiment, at least an uppersection 12 is mounted to a lower section 16. For units which requirefilter cartridges longer than the filter cartridge which can be arrangedin a spaced stacked arrangement in the two sections 12 and 16, middlefilter housing sections 14 are provided; and, any number of sections 14may be added to the stacking arrangement and is only defined by thevertical height of the filter cartridge as desired by the user.

[0030] In FIG. 5A, the lower section 16 is provided with inwardlyextending seal 17 which, as shown in FIG. 4B, receives the second dam 46thereon to prevent the flow or the intermingling of filtered effluent inthe chamber 28 with the incoming waste water flowing upwards through theopening 119. The lower section 16 is provided with lobes 54 c which arefor alignment with lobes 54 b in lower section 14 and lobes 54 a in theupper section 12. The upper portion of the lower section 16 is providedwith an inwardly extending step 16 b which receives the lowerterminating edge 14 a of the middle section 14 or the lower terminatingedge 12 a of the upper section 12. The lower terminating edges 12 a and14 a are of a reduced diameter from the diameter of the exposed outersurface of the remainder of housing portions 12 and 14, respectively.Moreover, the vertical height of the lower terminating edges 12 a and 14a are the same distance as the distance of the upper terminating edge 16a from section 16 from step 16 d. And, in a stacked arrangement theoutside or exposed outer surface of the diameter of the housing is ofthe same diameter from the upper section to the lower section.

[0031] As shown in FIG. 5B, the middle section is provided with lobes 54b which are for alignment with the lobes 54 c and 54 a and the sealmembers 24 b which extend vertically along the inner surface of thecylindrical housing section. As shown in the cut-out, middle housingsection 14 is provided with a step 14 b which is a preselected distancefrom the terminating edge 14 c to receive the lower terminating edge 14a of a middle filter housing section 14 or the lower terminating edge 12a of an upper housing section 12.

[0032] As shown in FIG. 5C, an upper section 12 is provided with theoutlet 18 which is comprised of a plurality of rings 20 and 22 to attachto a waste water treatment tank outlet 14. Upper section 12 is alsoprovided with lobes 54 a for alignment with lobes 54 b and 54 c andengagement with the cut-outs 52 in the discs 32, 132. Sealing members 24a are also provided for engagement with the terminating edges 34 a and bof the disc 32.

[0033] An alternative disc filter element 332 is depicted in FIG. 7. Ascan be seen therein, first filtering dam 36 extends upward from baseportion or planar surface 340. First filtering dam 36 is again ofserpentine construction. Flow through apertures 38 are formed throughbase portion 340 and are formed between the serpentine curvatures of thefirst dam. The serpentine curvatures extend the length of the first dam36 between first end 34 a and second end 34 b.

[0034] Second dam or weir 346 is similarly provided extending betweenthe first and second end 34 a, 34 b of the first dam. The first dam 36extends between the flow through apertures 38 and the second dam 346.The second dam 346 is provided in order to reduce the flow rate of thewater passing through the filter element 332 which is stacked in aplurality within the filter housing. Fluid passing through the disc-damfilter element 332 first is filtered through apertures 38, causingparticulate material to sluff downward through the vertical columndefined by the apertures 38 and the plurality of units stacked together,as mentioned above. A plurality of vertical notches 345 are formed inthe second dam in order to allow fluid therein to drain appropriatelyinto chamber 28 and outlet discharge 19 depicted in the other Figures.Notches 345 ensure that no fluid remains undrained in the centralportion of base section 340 after removal of the stacked filter unit.Notches 345 are approximately {fraction (5/32)} inch in width in orderto properly filter retain larger particles on base portion 340. Notches345 act to allow water to flow over planar base portion 340 at a slowerrate than if the weir or second dam 346 were not present. Further, theslower flow rate causes material suspended in the fluid to separate andcome to rest on the base portion 340. Each of the filter elements 332are vertically stackable upon one another by the interlocking connectors50 which separate each of the base portions 340 and top edge 44 of firstdam by a slight gap to allow filtered fluid therethrough.

[0035] By placement of the notches 345 in second dam 346, fluidcontained or trapped therein will drain appropriately. This will beparticularly the case with the filter sections are removed from thehousing. Upward lifting of the stacked filter sections causes the fluidto drain from the individual disc filter element 332 such that removalof the stacked filter elements will not also remove correspondingamounts of fluid from the filter housing. Additionally, as depicted inFIG. 7, cylindrical bore support member 347 is provided to extendupwardly and downwardly from the base portion 340 in order to provide anadditional support area for each filter disc-dam unit 332 and receivesupport pipe 60. Thus, the units have four support points, each of thethree interlocking connectors 50 and the bore support member 347.

[0036] In operation, as shown in FIGS. 3, 4A, 4B and 6, waste waterenters the waste water treatment tank 2 through a waste water inlet 8.Tank 2 generally includes at least one or more openings thereinidentified by the numeral 4 with a cover 6 thereover which provide forentrance to the tank. At least one opening 4 is shown in alignment witha filter housing 10 for easy removal of the sections 12, 14, 16 or discs32 in filter housing 10. The waste water entering the tank 2 fills untilthe level 9 is reached which is in alignment with the waste waterdischarge outlet 19. The flow of the waste water is up through the lowerfilter section 16 and is discharged through the outlet 18 in the uppersection 12. As the waste water discharge flows into the filter housingthrough the opening 119, the waste water, as shown by the arrows, movesupwardly adjacent to the central portion of the cartridge unit throughthe slotted openings 38 in the discs 32. The waste water flowing upwardsthrough the slots 38 provides for the settling of the particles, whichflow downwardly through the slots 38, as the rising waste water movesupwardly through the slots 38 and over flows the top edges 44 of thedams 36. Spacing between the top edge 44 and the under surface 42 of anoverlying disc 32 is of a preselected distance, generally less than an⅛″, so that only very small particles have the opportunity to overflowthe top edge 44. Overflowing waste water is filtered at the selectedspacing between the under surface 42 and the top edge of the underlyingdam top 44 so that relatively clean water exits, into the chamber 28 andout through the outlet discharge 19. By arranging the slots 38 in thecurvature of the serpentine configured dam 36 there is little to noturbulence and the turbulence is minimized at the dam top 44 overflow.Also, it has been found that this reduced turbulence promotes “sluffing”at the interior column because of this lack of turbulence created by thewater moving across the upstream surface of the disc as the dynamics ofthe water is flowing in a vertical condition and not in a vertical andhorizontal condition.

[0037] The foregoing detailed description is given primarily forclearness of understanding and no unnecessary limitations are to beunderstood therefrom for modifications will become obvious to thoseskilled in the art upon reading this disclosure and may be made withoutdeparting from the spirit of the invention and scope of the appendedclaims.

1. A waste water treatment filter system comprising: a housing having anoutlet for flow communication with a waste water treatment tankdischarge outlet and on open bottom, said housing including means toreceive a plurality of disc-dam units therein; said plurality ofdisc-dam units being in a stacked arrangement to define a filtercartridge having a vertically extending longitudinal axis extending fromthe top of said housing to a lower portion of said housing, each saiddisc-dam unit being of a generally circular-shaped disc having an outerterminating edge with a cut-out cord segment, the disc-dam unitcomprising a base portion having a planar under surface and an uppersurface with a first dam of serpentine configuration having a first endand a second end, said dam extending upwards from said upper surface andterminating in a dam top, said first end and said second end definingsaid cord segment therebetween, said first dam dividing said base intoupstream and downstream sides, said upstream side being along an outerperiphery of said base and said downstream side being along an innerperiphery of said base, said cord segment having a second dam connectingsaid first end and said second end, said second dam having a height lessthan the height of said first dam, each of said discs having a pluralityof openings in said upstream side in flow communication with an adjacentlower disc-dam unit, said cut-outs being aligned to form an outlet flowchamber in flow communication with said housing outlet.
 2. The system ofclaim 1, each of said disc-dam units having a diameter of about ⅛″ lessthan the inside diameter of said housing.
 3. The system of claim 1wherein said means to receive disc-dam units includes a plurality ofvertically extending lobes extending continuously along the innersurfaces of said upper section and said lower sections, each disc havingnotches in mating relations with said lobes.
 4. The system of claim 1,wherein said second dam height is approximately one-half the height ofsaid first dam height.
 5. The system of claim 1, each disc-dam unithaving a centrally disposed opening with a vertically extending pipereceived through said centrally disposed opening, saidvertically-extending pipe having a closed top and a closed bottom. 6.The system of claim 1, said upstream openings being disposed at curvedportions within said serpentine configuration.
 7. The system of claim 1,each said disc-dam unit terminating edge being adjacent an inner surfaceof one of said upper section and said lower section.
 8. The system ofclaim 1, said housing comprising: an upper section with an outlet forflow communication with a waste water treatment tank discharge outletand a lower section with an open bottom, said upper section beingcoaxially mounted above said lower section, said upper section and saidlower section including means to receive a plurality of disc-dam unitstherein, said upper section outlet having at least two outwardlyextending co-axial rings of different diameters; said lower sectionhaving an inwardly extending sealing edge positioned for alignment withdisc-dam unit cut-outs, said sealing edge being in contacting relationwith a lowermost disc-dam unit, said sealing edge covering said cut-outof said lowermost disc-dam unit thereby sealing the bottom of saidoutlet flow chamber.
 9. The system of claim 8 including at least onemiddle section, said middle section mounted between said upper sectionand said lower section, said middle section having means to receive saiddisc-dam units therein.
 10. The system of claim 1, said upper sectionoutlet having at least two outwardly extending co-axial rings ofdifferent diameters.
 11. The system of claim 10, said rings being ofpreselected size and thickness to receive waste water discharge outletsof a plurality of various diameters.
 12. The system of claim 1 whereinat least one of said disc-dam units includes a second cut-out therein,said disc-dam unit including said second cut-out being positionedadjacent a top of said upper section.
 13. A wastewater treatment filtercomprising: a plurality of stackable filter elements, each of saidelements having a base portion having a plurality of flow throughapertures formed therethrough; a first filtering dam and secondfiltering dam; at least one interlocking connector extending upward fromsaid base portion; wherein said first dam extends between said flowthrough apertures and said second dam.
 14. The filter of claim 13wherein each of said filter elements further comprises at least one flowthrough notch formed in said second dam.
 15. The filter of claim 13wherein said first dam extends upwardly from said base portion and has afirst end and a second end.
 16. The filter of claim 15 wherein saidsecond dam extends between said first and said second end of said firstdam.
 17. The filter of claim 15 wherein said first dam is a serpentineconfigured dam.
 18. The filter of claim 17 wherein said second damextends between said first end and said second end of said serpentinedam.
 19. The filter of claim 17 wherein said flow through apertures areeach formed between curvatures formed in said first dam.
 20. The filterof claim 16 wherein said first dam has a vertical height which is lessthan the vertical height of said at least one interlocking connector.21. The filter of claim 20 wherein said second dam has a vertical heightwhich is less than said vertical height of said first dam.
 22. Thefilter of claim 16 wherein said base portion is a circular shaped disc.23. The filter of claim 21 wherein said vertical height of said seconddam is about one-half the vertical height of said first dam.
 24. Thefilter of claim 13 further comprising a support bore extending upwardand downward from said base.